There is a problem in the drawing template. Open the template. Edit Sheet 1's properties. Make sure a sheet format is selected. Click OK. Save the template.
Sorry for the bump. Next person to wrestle with this error now has a good answer. =)
Hi, I had all of the same problems as listed here and tried many of the suggested work-arounds (all of which were unsuccessful).
I believe the problem was caused by me deleting old solidworks installation directories (e.g C:\ProgramData\SolidWorks\SolidWorks 2008) after i upgraded to SW 2010.
I simply re-created the deleted directory and copied & pasted my templates (sldrt files etc) to the new directory. (this tricked SW) and i can now create new sheets with my custom sheet formats.
I know this is an old post, but I posted a video tip recently on this topic:
Hope this helps,
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